This invention relates to dispensers, and specifically to a flexible sheet material dispenser, such as useable for dispensing paper towels, and a mechanism adapted to be used therein for cutting a web of flexible sheet material into individual lengths of the material.
Dispensers for flexible sheet material, such as paper toweling have long been known to include mechanisms for perforating or severing a web of such material to divide the web into individual sheets. Generally the perforating or severing mechanisms used in these dispensers include a rotatably mounted knife and a cooperating rotatably mounted roller having a slot therein for receiving the radially outward portion of the knife as the knife rotates past the roller. The web of flexible sheet material is passed between the roller and the knife to be perforated or severed when the radially outward knife portion enters the slot in the roller.
Such mechanisms are satisfactory for perforating or severing relatively unstretchable flexible sheet materials, such as uncreped paper toweling. However, with the increased use of relatively stretchable flexible sheet materials, such as embossed and creped paper toweling, the prior art perforating and severing mechanisms have proved unsatisfactory because the web of sheet material tends to stretch about the cutting edge of the knife instead of being perforated or severed thereby. Although precession rotary shears are known which could be employed for obviating this problem, such shears are much to expensive to be used in flexible sheet material dispensers designed for installation to be used in both commercial and private washrooms.